he did not find it after all, was, perhaps, because his fairy guide, Imagination, was not sufficiently well-grown, or well-educated, to direct him aright. I observed, just now, that, in fact, there had been certain vague attempts at referring Gravity to some very uncertain _isms_. These attempts, however, although considered bold and justly so considered, looked no farther than to the generality—the merest generality—of the Newtonian Law. Its _modus operandi_ has never, to my knowledge, been approached in the way of an effort at explanation. It is, therefore, with no unwarranted fear of being taken for a madman at the outset, and before I can bring my propositions fairly to the eye of those who alone are competent to decide upon them, that I here declare the _modus operandi_ of the Law of Gravity to be an exceedingly simple and perfectly explicable thing—that is to say, when we make our advances towards it in just gradations and in the true direction—when we regard it from the proper point of view. Whether we reach the idea of absolute _Unity_ as the source of All Things, from a consideration of Simplicity as the most probable characteristic of the original action of God;—whether we arrive at it from an inspection of the universality of relation in the gravitating phænomena;—or whether we attain it as a result of the mutual corroboration afforded by both processes;—still, the idea itself, if entertained at all, is entertained in inseparable connection with another idea—that of the condition of the Universe of stars as we _now_ perceive it—that is to say, a condition of immeasurable _diffusion_ through space. Now a connection between these two ideas—unity and diffusion—cannot be established unless through the entertainment of a third idea—that of _irradiation_. Absolute Unity being taken as a centre, then the existing Universe of stars is the result of _irradiation_ from that centre. Now, the laws of irradiation are _known_. They are part and parcel of the _sphere_. They belong to the class of _indisputable geometrical properties_. We say of them, “they are true—they are evident.” To demand _why_ they are true, would be to demand why the axioms are true upon which their demonstration is based. _Nothing_ is demonstrable, strictly speaking; but _if_ anything _be_, then the properties—the laws in question are demonstrated. But these laws—what do they declare? Irradiation—how—by what steps does it proceed outwardly from a centre? From a _luminous_ centre, _Light_ issues by irradiation; and the quantities of light received upon any given plane, supposed to be shifting its position so as to be now nearer the centre and now farther from it, will be diminished in the same proportion as the squares of the distances of the plane from the luminous body, are increased; and will be increased in the same proportion as these squares are diminished.